Automatic circuit bbeakeb



C sept. 27,1927. 1,643,415

E. D. MOORE.

AUTOMATIC CIRCUIT BREAKER Filed Sept. 14, 1923 2 Sheets-Sheet l il@ d IIIII M `C, afp/LL..

sept.. "27, 192,7.

EV. D. AMOOFEE AUTOMATIC CIRCUIT BREAKER Filed Slept- 14, 1925 2 Sheets-Sheet 2 Patented Sept. 27, 1927.

UNITED STAT-Es 1,543,415 P'Arsur orties.

v EDGAR D. MOORE, OFCLEVELAND, OHIO. n

AUTOMATIC omonir Bananen.

Application filed September 14, 1923. Serial No. 662,663.

ner if the operator attempts to reset the device before removing an excessive load from the circuit, andhence no damage will result from such resetting.

Another lobject is to provide a circuit breaker, the parts whereof may be so arranged and set, that the device will be sensitive to an exceedingly small current, or if desired may be set for larger currents and will operate to open the circuit by a current slightly in excess of the normal loadsetting. V

A still further object is lto provide a circuit breaker ofthe aforesaid character which Vshall be simple in construction, inexpensive to manufacture and which shall be thoroughly reliablein operation.

With these and other objects inview, the invention consists in the various novel features of construction and arrangement or combinatiom, all of which willbe fully described hereinafter and pointed out in the appended claims.

In t-lie'aocompanying' drawings forming part of this application and wherein I have shown certain illustrative forms of my invention Figs. 1 and 2 are vertical sectional l views of a circuit breaker constructed in accordan'ce with my invention and showing the same in closed circuit position and open circuit position respectively; Fig.V 3 is a similar view but showing the main contacts" in closed circuit position and the auxiliary contacts in open circuit position; Fig. 4 isa transverse sectional view taken on the line 4-4 of Fig. 1?; Fig. 5 is an enlarged detailedv sectional view taken on theline 5--5 of Fig, 4; Fig. 6 is a transverse sectional'view through the main contacts; and Fig. 7 is a vertical sectional view through a modied form of vcircuit breaker which 1s adapted means of screws 16 as shown in Fig. 4.

"that the auxiliary contacts in the present inespecially for protecting circuits carrying a small current value. i

Describing the various parts by reference characters 1 denotes the usual or standard -Edison base plug consisting `of an outerV threaded sleeve '2 and a central contact 3. These' contacts are separated by an insulating body 4 which is provided adjacent one end with a collar v5 and a recess 6. i Disposed within recess 6 are a pair of stationary contacts 7, one Vof which is connected `with' Contact 3 and the other is connected `through a screw 8 with threaded sleeve 2.

These contacts are adapted to be engaged by a pair of movable contacts to be referred to hereinafter. housing '10 encloses the contacts and at one endV thereof is provided with an inturned flange 11 whicheinbraces collar 5, and atthe opposite end, said housing is provided with an out-turned .flange i12. A washer 13 of insulating material, a

washer 14`of magnetic material, and a casing 15 of magnetic material are secured to the flange 12 in any suitable manner as by Disposed within casing '15' is a'solenoid "windingl which is wound about a :non-

magnetic sleeve 18 and insulated from said sleeve and casing by paper 191er other suitable material. Sleeve 18 is preferably'split longitudinally to prevent current being induced therein which wouldlcause said sleeve to heat.V One 'end ofthe winding 17'is connected toa movable contact spring 20 while :the other endl of said winding is `connected through a pair of auxiliary contacts toa movablec'ontact spring 21.V f

Referring to Figs. 4 and 5 itwill be noted stance'consist of a pair of screws threaded into washer 13 'and a second pair ofscrews 24 threaded into an insulating plate 25. This.

plate is guided vin its movement by a pairof screws 26 passing therethrough and threaded into the'washer 13, and a spring 27 interi posed between the head of each screw 26 and plate 25, normally urges contacts Q4 into engagement with contact-s 23.

A plunger 80' forinedfroni magnetic material is slidably disposed within' sleeve 1S and adjacent one end `thereof said plunger is reduced in diameter as indicated at 31. l

A rnon-inagnetic rod'32 is slidable longitudinally with respect tothe-plunger and such Ylongitudinalmovement is limited by a transverse pin 33 which is disposed in a slot 34 formed in the plunger. This pin is adapted to engage the plate 25 to force said plate inwardly when the rod 32 is depressed by means of a knob 35. rlhe inner end of plunger is slotted as indicated at 36 (Fig. 6) to receive an insulating arm 37 which is pivotally connected to the plunger and to movable contact 21. A similar pair of insulating arms 38 are pivotally connected to the plunger and also to movable contact 20 as shown in Fig` 6.

Assuming that the parts of the device are in the position shown in Fig. 2, the operator pushes inwardly on knob to set the contacts and complete the circuit through the device. causes pin 33 to contact with the end of slot 34 and carry the plunger inwardly thereby straightening the toggle arms 37 and 35% and forcing movable contacts 2O and 2l into engagement with their respective stationary contacts 7. Meanwhile thc pin 33 has engaged plate 25 and forced said plate inwardly against the tension of springs 27 and opened the auxiliary contacts 23 and 24 as shown in Fig. 3 before the main contacts 2O and 2l have engaged with their respective contacts 7. The operator now releases the knob, and the toggle arms being beyond their pivotal center line, the contacts 2O and 7, and 21 and 7, remain closed, while the springs 27 force the rod 32 outwardly and close contacts 23 and 24 and the device assumes the position shown in Fig. 1. Cnr-v rent will now flow from the source through one of the contacts of the base plug, as for example, the central contact 3, stationary contact 7, movable contact arm 20, solenoid winding 17, one of the pairs of contacts 23 and 24, through a wire 40 (Fig. 4) to the other contact 24, thence through the other contact 23 to movable contact arm 21 and stationary contact 7, screw 8 and threaded sleeve 2 of the base plug. rllhe normal flow of current through solenoid winding 17 will be insufficient to attract plunger 30 and hence the contacts will remain closed. If an excessive load is imposed on the circuit, the solenoid winding will exert suiiicient outward pull on the plunger to trip the toggle and forcibly separate the arms 20 and 21 from their respective contacts 7 thereby opening the circuit.

If the operator should attempt to reset the device before the excessive loa-d has been removed from the circuit, no harm Ywill be done as it will be remembered that contacts 23 and 24 open before contacts 2O and 2l close with contacts 7 and hence current cannot flow through the device until the parts of the device are in their normal closed circuit position whereupon the excessive flow of current will trip the device as before.

The function of themagnetic casing 15 The inward movement of rod 32 cuits carrying relatively small currents. ln

this form, the center of plunger 30a is located near lthe center of the winding 17a so that the plunger will be subjected to a strong magnetic pull when the solenoid is energized above normal. In order to simplify the construction of the device I preferably provide plunger 30a with a bore 43 which terminates adjacent one end of said plunger to define a wall 44. This wall is bored to slidably receive a screw r45, the head whereof .is disposed within bore 43 and the opposite end thereof is threaded into a stem 46 which is connected through toggle arms 37 and 38a to contact springs 2Oa and 21a as previously described. A non-magnetic stem 47 is threaded in the opposite end of plunger and this stein is fitted with `a knob 35a.

The auxiliary contacts in this instance are adapted to be connected by a metallic element 48 which is insulated from the plunger 30a by a washer 49 formed from insulating material.

The operation of the device will be similar to that previously described. In this instance, however, the inward movement of plunger 30a will be transmitted through washer 49 to plate 48 to separate the auy iary contacts and contained inward movement will engage said plate with stein 4 6 and reset the toggleV arms as previously ein plained. An excessive flow of current through the solenoid winding` will move plunger 3()a inwardly and carry screw 45 and stem 46 inwardly therewith to break the toggle `joint .and open the main contacts in the usual manner.

Having thus described my invention, what I claim is 1. An electromagnetic switch of the character described comprising a housing having main and auxiliary contacts, a plunger having ar toggle arm connection and adapted to be manually operated to close said main contacts, a platecarried by said plunger for closing said auxiliary contacts, .said plate being movable with said plunger whereby said auxiliary contacts are opened before said main contacts can be closed, and a solenoid in said housing adapted toactuate said plunger to break said main contacts upon certain predetermined conditions.

2. An electromagnetic switch of the character set forth comprising a housing having a pair of terminal contacts, electromagnetic means carried by said housing, the winding of said electromagnetic means being connected through a .pair of 'movable contacts with the terminal contacts of said housing, a toggle connecting said movable contacts, an element responsive to said electromagnetic means, said element being connected to said toggle and adapted to open said contacts when the current flowing through said electromagnetic means exceeds a predetermined value, and means for automatically opening said electromagnetic circuit during the resetting of said movable contacts and closing said circuit after said movable contacts are reset.

3. An electromagnetic switch of the character set forth comprising a housing having a pair of terminal contacts, electromagnetic means carried by said housing, the winding of said electromagnetic means being connected through a pair of movable contacts with the terminal contacts of said housing, a toggle connecting said movable contacts, an element responsive to said electromagnetic means, said element being connected to said toggle and adapted to open said contacts when the current iiowing through said electromagnetic means exceeds a predetermined value, and a second contact adapted to be actuated by said element thereby to automatically open said electromagnetic circuit during the resetting of said movable contacts and close said circuit after said movable contacts are reset.

4. An electromagnetic switch of the character set forth comprising a housingrhaving a pair of terminal contacts, a solenoid carried by said housing, a pair of main contacts normally in circuit with said terminal contacts, a plunger adapted to be actuated by said solenoid to break the circuit, a toggle joint connection between said main contacts and said plunger, an auxiliary contact nor-A mally .in circuit ywith said main contacts comprising a plate carried by said plunger,

said platebeing so connected with said' plunger as to be moved thereby to break said auxiliary contacts before said main contacts `can be closed.

5. An electromagnetic'switch,of the character set forth comprising a housing having a pair of terminal contacts, a solenoid carried by said housing, a pair of main conried by said housing, a pair of main contacts in circuit with the terminal contacts of said housing, a plunger adapted to be actuated by said solenoid, a toggle joint connection between said main contacts and said plunger,

anauxiliary Contact in electrical circuit with said -inain contactsand said solenoid, said auxiliary Contact being adapted to be engaged by said plunger to open said solenoid circuit during the resetting of said main contacts, and means for automatically closing said auxiliary contact after the main contacts are reset. y

In testimony whereof, I hereuntoaifix my signature. Y

' lEDGAR D. MOORE. 

